A five-step synthesis of the water-soluble chiral polydentate ligand,(S)-PDTA [(S)-PDTA= N, N, N′, N′-tetrakis [(hydroxycarbonyl) methyl]-(S)-1, 2-diaminopropane] starting from l- alanine has been worked out, via steps with retention of chirality. Total yield is 50.7%(average of∼ 88% for each step), while published methods report 33.4% total yield over four steps.
